Having been asked about the possibility of the EU-US trade deal being signed under President Trump’s watch, Professor Malloch replied: “I personally am not certain that there will be a European Union with to have such negotiations.

“Will there potentially be numerous bi-lateral with various European countries? I think the prospect, again in a changed political reality, is greater for that.”

The American added: “I think people are talking about the redefinition of the European Union, whether it is a core number of countries and a periphery that moves aside, key people that stay in the Union, those that fall away.

“These are decisions that are going to be made by European people in democratic elections over the course of the next 18 months, and some of these elections, frankly, are coming as soon as the next few months.”

Prime Minister Theresa May, on Friday, will become the first foreign leader to visit the President, exactly a week after his inauguration.

The pair are expected to discuss Nato, immigration and, most importantly, a post-Brexit deal between the two nations, with President Trump previously spoken about striking such a deal as soon as possible.

Professor Malloch said that Britain could agree a “mutually beneficial” free trade deal with America in as little as 90 days.

He continued by saying that outside the single market and customs union, the UK could bypass “the bureaucrats in Brussels”, adding that it would be “absurd” that EU leaders attempt to block negotiations between the two nations.

Theresa May's 12 point Brexit plan
Mon, January 16, 2017

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Continued cooperation with the EU to tackle terrorism and international crime.

But Professor Malloch did say that Mrs May will leave the White House on Friday without a trade deal, he said: “Obviously there are things to iron out, certainly there are differences and compromises to make, but it can be done.

“There won’t be a deal signed in the White House on Friday, but there could be an agreement for a framework going forward where people are empowered to have that kind of conversations behind closed doors and it could take as little as 90 days.

“That is very positive and it sends a signal that the United States is behind Great Britain in its hour of need.”